* feat(test): add --clear-data flag to clear app data on launch
* test+docs: cover --clear-data flag in CLI parser test and reference
* feat(spec): type AttrSelector with known attribute names
Replace AttrSelector = Record<string, string> with KnownAttrSelectors
plus a string|boolean index signature, so authors get autocomplete and
type-checking on testTag / focused / clickable / etc. while raw driver
attributes still type-check via the fallback. Boolean state attributes
accept native booleans; goja stringifies them at the marshal boundary.
AccessibilityElement.attrs becomes RawAttrs (typed string-valued shape
of the same canonical names) so element.attrs.testTag autocompletes.
* test(verifier): native boolean selector value matches focused=true
* docs+folio: use native boolean for focused selector and document typed attrs
* docs(architecture): add device/emulator node and XCTest edge to diagram
* docs(manual): rewrite writing-specs with accurate API and updated examples
* docs(manual): add spec-language reference page
* docs(sidebar): add spec-language entry to sidebar nav
pj